1 sn The Lord here uses a metaphor from the realm of ritual purification. For the use of water in ritual cleansing, see Exod 30:19-20; Lev 14:51; Num 19:18; Heb 10:22.
2 sn That is, a heart which symbolizes a will that is stubborn and unresponsive (see 1 Sam 25:37). In Rabbinic literature a “stone” was associated with an evil inclination (b. Sukkah 52a).
3 sn That is, a heart which symbolizes a will that is responsive and obedient to God.